The Gross Vehicle Weight is only the truck plus cargo, it does not include any trailers. That would be gross Combined Vehicle weight Rating. A 3/4 ton or 1 ton will be more than capable of towing an 8300# trailer, however, anything that you can do to improve the braking system, especially if you plan on a Deisel, will help.
Don't expect much in the line of good road speed with either, though. Or at least not without changing the rear gear and/or adding an overdrive.
